The European Commission has yet to publish the level-two draft of the Markets in Financial Instruments Directive (MiFID), which was scheduled to be released before Christmas.
The delay puts pressure on bank IT directors, who will have even less time to make preparations for the directive, which is due to become law in November 2007.
MiFID will create a single European market for financial instruments and includes legislation to enforce best-execution principles and make traders publish all dealing prices in real time.
Bob Fuller, head of IT strategy at Dresdner Kleinwort Wasserstein and co-chair of the MiFID IT Joint Working Group, said the delay was causing real concern for IT directors across the trading community.
"Financial firms need to start taking practical steps to implement MiFID processes, but without confirmation of the directive most will choose not to embark on that programme," he said.
"Everything is in stasis at the moment, and the November 2007 deadline is looking ever tighter."